Mechanically robust SiC aerogel with both electromagnetic absorption and pollutant adsorption via microtube/nanowire structure design

With the rapid advancement of new energy, aerospace, and other technologies, equipment is increasingly subjected to harsh environments, placing extremely high demands on the multi-functional synergy of materials—including thermal management, mechanical load-bearing, and electromagnetic protection. Traditional aerogel materials often struggle to balance these properties, facing bottlenecks such as structural homogeneity, poor mechanical strength, and high production costs.

“We have long sought a versatile material that is exceptionally strong, resistant to extreme conditions, efficient at managing heat, and transparent to electromagnetic waves.” explained Chen Ma, corresponding author of the study. “Surprisingly, nature provided the inspiration. The natural hollow microtubular structure of kapok fibers offered a perfect template for constructing hierarchical porous channels.”

The key breakthrough of this research lies in a series of sophisticated chemical conversion processes that successfully transform low-cost kapok fibers into a three-dimensional network aerogel composed of intertwined silicon carbide microtubes and nanowires. This unique “microtube-nanowire” heterostructure is the core feature that imparts a range of outstanding properties to the material. The nanowires form countless “bridges” between the microtubes, significantly enhancing mechanical strength—making the compressive strength more than ten times greater than that of traditional aerogels. At the same time, the abundant interfaces and defects act as highly efficient “energy traps” capable of converting incident electromagnetic wave energy into heat, achieving broadband and strong absorption for stealth performance.

The team published their work in Journal of Advanced Ceramics on September 29, 2025.

Experimental results show that this new aerogel exhibits excellent electromagnetic wave absorption performance, with a minimum reflection loss as low as –56.39 dB, meaning it can absorb over 99.999% of incident electromagnetic waves. Its thermal insulation performance is equally impressive, with a thermal conductivity as low as 0.021 W·m⁻¹·K⁻¹ at room temperature. Even when exposed to flame at temperatures exceeding 1000°C, the backside remains cool, with a temperature difference of over 1000°C. After hydrophobic modification, the material can also rapidly adsorb floating oils and other organic pollutants from water surfaces, with an adsorption capacity 45 to 67 times its own weight, earning it the title of a “super sponge.”

When asked about the ultimate goal of the research, Chen Ma stated, “Our long-term goal has been to promote the practical application of this high-performance, low-cost multifunctional material. It holds promise as an ideal integrated thermal insulation and stealth material for thermal protection systems in hypersonic vehicles, or as an efficient adsorbent for environmental incidents such as marine oil spills.”

As for the next steps, the research team is focusing on optimizing the preparation process to enable large-scale, standardized production. They have also begun engaging with industrial partners to explore its practical application performance in specific equipment. They believe that this bio-inspired design, rooted in nature, will open new doors for the development of next-generation multifunctional materials.

This work was supported by the Scientific Research Funds of Huaqiao University (No. 23BS119), Natural Science Foundation of Fujian Province of China (No. 2024J01310690), National Natural Science Foundation of China (No. 52302064) and the Fundamental Research Funds for the Central Universities (No. ZQN-1204)

About Journal of Advanced Ceramics

Journal of Advanced Ceramics (JAC) is an international academic journal that presents the state-of-the-art results of theoretical and experimental studies on the processing, structure, and properties of advanced ceramics and ceramic-based composites. JAC is Fully Open Access, monthly published by Tsinghua University Press, and exclusively available via SciOpen. JAC’s 2024 IF is 16.6, ranking in Top 1 (1/33, Q1) among all journals in “Materials Science, Ceramics” category, and its 2024 CiteScore is 25.9 (5/130) in Scopus database. ResearchGate homepage: https://www.researchgate.net/journal/Journal-of-Advanced-Ceramics-2227-8508